1 |
tim |
1.1 |
/* |
2 |
dl |
1.6 |
* %W% %E% |
3 |
tim |
1.1 |
* |
4 |
jsr166 |
1.23 |
* Copyright 2005 Sun Microsystems, Inc. All rights reserved. |
5 |
tim |
1.1 |
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. |
6 |
|
|
*/ |
7 |
|
|
|
8 |
jsr166 |
1.24 |
package java.util; |
9 |
jsr166 |
1.36 |
import java.util.*; // for javadoc |
10 |
tim |
1.1 |
|
11 |
|
|
/** |
12 |
|
|
* Linked list implementation of the <tt>List</tt> interface. Implements all |
13 |
|
|
* optional list operations, and permits all elements (including |
14 |
|
|
* <tt>null</tt>). In addition to implementing the <tt>List</tt> interface, |
15 |
|
|
* the <tt>LinkedList</tt> class provides uniformly named methods to |
16 |
|
|
* <tt>get</tt>, <tt>remove</tt> and <tt>insert</tt> an element at the |
17 |
|
|
* beginning and end of the list. These operations allow linked lists to be |
18 |
dl |
1.19 |
* used as a stack, {@linkplain Queue queue}, or {@linkplain Deque |
19 |
|
|
* double-ended queue}. <p> |
20 |
tim |
1.1 |
* |
21 |
dl |
1.17 |
* The class implements the <tt>Deque</tt> interface, providing |
22 |
dl |
1.3 |
* first-in-first-out queue operations for <tt>add</tt>, |
23 |
dl |
1.21 |
* <tt>poll</tt>, along with other stack and deque operations.<p> |
24 |
tim |
1.1 |
* |
25 |
|
|
* All of the operations perform as could be expected for a doubly-linked |
26 |
|
|
* list. Operations that index into the list will traverse the list from |
27 |
dl |
1.8 |
* the beginning or the end, whichever is closer to the specified index.<p> |
28 |
tim |
1.1 |
* |
29 |
|
|
* <b>Note that this implementation is not synchronized.</b> If multiple |
30 |
|
|
* threads access a list concurrently, and at least one of the threads |
31 |
|
|
* modifies the list structurally, it <i>must</i> be synchronized |
32 |
|
|
* externally. (A structural modification is any operation that adds or |
33 |
|
|
* deletes one or more elements; merely setting the value of an element is not |
34 |
|
|
* a structural modification.) This is typically accomplished by |
35 |
|
|
* synchronizing on some object that naturally encapsulates the list. If no |
36 |
|
|
* such object exists, the list should be "wrapped" using the |
37 |
|
|
* Collections.synchronizedList method. This is best done at creation time, |
38 |
|
|
* to prevent accidental unsynchronized access to the list: <pre> |
39 |
|
|
* List list = Collections.synchronizedList(new LinkedList(...)); |
40 |
jsr166 |
1.24 |
* </pre> |
41 |
tim |
1.1 |
* |
42 |
jsr166 |
1.24 |
* <p>The iterators returned by this class's <tt>iterator</tt> and |
43 |
tim |
1.1 |
* <tt>listIterator</tt> methods are <i>fail-fast</i>: if the list is |
44 |
jsr166 |
1.24 |
* structurally modified at any time after the iterator is created, in |
45 |
|
|
* any way except through the Iterator's own <tt>remove</tt> or |
46 |
|
|
* <tt>add</tt> methods, the iterator will throw a {@link |
47 |
|
|
* ConcurrentModificationException}. Thus, in the face of concurrent |
48 |
|
|
* modification, the iterator fails quickly and cleanly, rather than |
49 |
|
|
* risking arbitrary, non-deterministic behavior at an undetermined |
50 |
|
|
* time in the future. |
51 |
tim |
1.1 |
* |
52 |
|
|
* <p>Note that the fail-fast behavior of an iterator cannot be guaranteed |
53 |
|
|
* as it is, generally speaking, impossible to make any hard guarantees in the |
54 |
|
|
* presence of unsynchronized concurrent modification. Fail-fast iterators |
55 |
dl |
1.3 |
* throw <tt>ConcurrentModificationException</tt> on a best-effort basis. |
56 |
tim |
1.1 |
* Therefore, it would be wrong to write a program that depended on this |
57 |
|
|
* exception for its correctness: <i>the fail-fast behavior of iterators |
58 |
jsr166 |
1.24 |
* should be used only to detect bugs.</i> |
59 |
dl |
1.3 |
* |
60 |
jsr166 |
1.24 |
* <p>This class is a member of the |
61 |
dl |
1.3 |
* <a href="{@docRoot}/../guide/collections/index.html"> |
62 |
|
|
* Java Collections Framework</a>. |
63 |
tim |
1.1 |
* |
64 |
|
|
* @author Josh Bloch |
65 |
dl |
1.6 |
* @version %I%, %G% |
66 |
jsr166 |
1.14 |
* @see List |
67 |
|
|
* @see ArrayList |
68 |
|
|
* @see Vector |
69 |
|
|
* @see Collections#synchronizedList(List) |
70 |
tim |
1.1 |
* @since 1.2 |
71 |
dl |
1.10 |
* @param <E> the type of elements held in this collection |
72 |
tim |
1.1 |
*/ |
73 |
|
|
|
74 |
dl |
1.3 |
public class LinkedList<E> |
75 |
|
|
extends AbstractSequentialList<E> |
76 |
dl |
1.17 |
implements List<E>, Deque<E>, Cloneable, java.io.Serializable |
77 |
tim |
1.1 |
{ |
78 |
dl |
1.3 |
private transient Entry<E> header = new Entry<E>(null, null, null); |
79 |
tim |
1.1 |
private transient int size = 0; |
80 |
|
|
|
81 |
|
|
/** |
82 |
|
|
* Constructs an empty list. |
83 |
|
|
*/ |
84 |
|
|
public LinkedList() { |
85 |
|
|
header.next = header.previous = header; |
86 |
|
|
} |
87 |
|
|
|
88 |
|
|
/** |
89 |
|
|
* Constructs a list containing the elements of the specified |
90 |
|
|
* collection, in the order they are returned by the collection's |
91 |
|
|
* iterator. |
92 |
|
|
* |
93 |
jsr166 |
1.27 |
* @param c the collection whose elements are to be placed into this list |
94 |
|
|
* @throws NullPointerException if the specified collection is null |
95 |
tim |
1.1 |
*/ |
96 |
jsr166 |
1.35 |
public LinkedList(Collection<? extends E> c) { |
97 |
|
|
this(); |
98 |
|
|
addAll(c); |
99 |
|
|
} |
100 |
tim |
1.1 |
|
101 |
|
|
/** |
102 |
|
|
* Returns the first element in this list. |
103 |
|
|
* |
104 |
jsr166 |
1.27 |
* @return the first element in this list |
105 |
|
|
* @throws NoSuchElementException if this list is empty |
106 |
tim |
1.1 |
*/ |
107 |
dl |
1.3 |
public E getFirst() { |
108 |
jsr166 |
1.14 |
if (size==0) |
109 |
|
|
throw new NoSuchElementException(); |
110 |
tim |
1.1 |
|
111 |
jsr166 |
1.14 |
return header.next.element; |
112 |
tim |
1.1 |
} |
113 |
|
|
|
114 |
|
|
/** |
115 |
|
|
* Returns the last element in this list. |
116 |
|
|
* |
117 |
jsr166 |
1.27 |
* @return the last element in this list |
118 |
|
|
* @throws NoSuchElementException if this list is empty |
119 |
tim |
1.1 |
*/ |
120 |
dl |
1.3 |
public E getLast() { |
121 |
jsr166 |
1.14 |
if (size==0) |
122 |
|
|
throw new NoSuchElementException(); |
123 |
tim |
1.1 |
|
124 |
jsr166 |
1.14 |
return header.previous.element; |
125 |
tim |
1.1 |
} |
126 |
|
|
|
127 |
|
|
/** |
128 |
|
|
* Removes and returns the first element from this list. |
129 |
|
|
* |
130 |
jsr166 |
1.27 |
* @return the first element from this list |
131 |
|
|
* @throws NoSuchElementException if this list is empty |
132 |
tim |
1.1 |
*/ |
133 |
dl |
1.3 |
public E removeFirst() { |
134 |
jsr166 |
1.14 |
return remove(header.next); |
135 |
tim |
1.1 |
} |
136 |
|
|
|
137 |
|
|
/** |
138 |
|
|
* Removes and returns the last element from this list. |
139 |
|
|
* |
140 |
jsr166 |
1.27 |
* @return the last element from this list |
141 |
|
|
* @throws NoSuchElementException if this list is empty |
142 |
tim |
1.1 |
*/ |
143 |
dl |
1.3 |
public E removeLast() { |
144 |
jsr166 |
1.14 |
return remove(header.previous); |
145 |
tim |
1.1 |
} |
146 |
|
|
|
147 |
|
|
/** |
148 |
jsr166 |
1.36 |
* Inserts the specified element at the beginning of this list. |
149 |
dl |
1.3 |
* |
150 |
jsr166 |
1.36 |
* @param e the element to add |
151 |
tim |
1.1 |
*/ |
152 |
jsr166 |
1.25 |
public void addFirst(E e) { |
153 |
|
|
addBefore(e, header.next); |
154 |
tim |
1.1 |
} |
155 |
|
|
|
156 |
|
|
/** |
157 |
jsr166 |
1.36 |
* Appends the specified element to the end of this list. |
158 |
|
|
* |
159 |
|
|
* <p>This method is equivalent to {@link #add}. |
160 |
dl |
1.3 |
* |
161 |
jsr166 |
1.36 |
* @param e the element to add |
162 |
tim |
1.1 |
*/ |
163 |
jsr166 |
1.25 |
public void addLast(E e) { |
164 |
|
|
addBefore(e, header); |
165 |
tim |
1.1 |
} |
166 |
|
|
|
167 |
|
|
/** |
168 |
|
|
* Returns <tt>true</tt> if this list contains the specified element. |
169 |
|
|
* More formally, returns <tt>true</tt> if and only if this list contains |
170 |
jsr166 |
1.28 |
* at least one element <tt>e</tt> such that |
171 |
|
|
* <tt>(o==null ? e==null : o.equals(e))</tt>. |
172 |
tim |
1.1 |
* |
173 |
jsr166 |
1.27 |
* @param o element whose presence in this list is to be tested |
174 |
|
|
* @return <tt>true</tt> if this list contains the specified element |
175 |
tim |
1.1 |
*/ |
176 |
|
|
public boolean contains(Object o) { |
177 |
|
|
return indexOf(o) != -1; |
178 |
|
|
} |
179 |
|
|
|
180 |
|
|
/** |
181 |
|
|
* Returns the number of elements in this list. |
182 |
|
|
* |
183 |
jsr166 |
1.27 |
* @return the number of elements in this list |
184 |
tim |
1.1 |
*/ |
185 |
|
|
public int size() { |
186 |
jsr166 |
1.14 |
return size; |
187 |
tim |
1.1 |
} |
188 |
|
|
|
189 |
|
|
/** |
190 |
jsr166 |
1.24 |
* Appends the specified element to the end of this list. |
191 |
tim |
1.1 |
* |
192 |
jsr166 |
1.36 |
* <p>This method is equivalent to {@link #addLast}. |
193 |
|
|
* |
194 |
jsr166 |
1.27 |
* @param e element to be appended to this list |
195 |
|
|
* @return <tt>true</tt> (as per the spec for {@link Collection#add}) |
196 |
tim |
1.1 |
*/ |
197 |
jsr166 |
1.26 |
public boolean add(E e) { |
198 |
|
|
addBefore(e, header); |
199 |
tim |
1.1 |
return true; |
200 |
|
|
} |
201 |
|
|
|
202 |
|
|
/** |
203 |
jsr166 |
1.28 |
* Removes the first occurrence of the specified element from this list, |
204 |
|
|
* if it is present. If this list does not contain the element, it is |
205 |
|
|
* unchanged. More formally, removes the element with the lowest index |
206 |
|
|
* <tt>i</tt> such that |
207 |
|
|
* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt> |
208 |
|
|
* (if such an element exists). Returns <tt>true</tt> if this list |
209 |
|
|
* contained the specified element (or equivalently, if this list |
210 |
|
|
* changed as a result of the call). |
211 |
tim |
1.1 |
* |
212 |
jsr166 |
1.27 |
* @param o element to be removed from this list, if present |
213 |
jsr166 |
1.28 |
* @return <tt>true</tt> if this list contained the specified element |
214 |
tim |
1.1 |
*/ |
215 |
|
|
public boolean remove(Object o) { |
216 |
|
|
if (o==null) { |
217 |
dl |
1.3 |
for (Entry<E> e = header.next; e != header; e = e.next) { |
218 |
tim |
1.1 |
if (e.element==null) { |
219 |
|
|
remove(e); |
220 |
|
|
return true; |
221 |
|
|
} |
222 |
|
|
} |
223 |
|
|
} else { |
224 |
dl |
1.3 |
for (Entry<E> e = header.next; e != header; e = e.next) { |
225 |
tim |
1.1 |
if (o.equals(e.element)) { |
226 |
|
|
remove(e); |
227 |
|
|
return true; |
228 |
|
|
} |
229 |
|
|
} |
230 |
|
|
} |
231 |
|
|
return false; |
232 |
|
|
} |
233 |
|
|
|
234 |
|
|
/** |
235 |
jsr166 |
1.24 |
* Appends all of the elements in the specified collection to the end of |
236 |
tim |
1.1 |
* this list, in the order that they are returned by the specified |
237 |
|
|
* collection's iterator. The behavior of this operation is undefined if |
238 |
|
|
* the specified collection is modified while the operation is in |
239 |
jsr166 |
1.33 |
* progress. (Note that this will occur if the specified collection is |
240 |
|
|
* this list, and it's nonempty.) |
241 |
tim |
1.1 |
* |
242 |
jsr166 |
1.31 |
* @param c collection containing elements to be added to this list |
243 |
jsr166 |
1.27 |
* @return <tt>true</tt> if this list changed as a result of the call |
244 |
|
|
* @throws NullPointerException if the specified collection is null |
245 |
tim |
1.1 |
*/ |
246 |
dl |
1.3 |
public boolean addAll(Collection<? extends E> c) { |
247 |
tim |
1.1 |
return addAll(size, c); |
248 |
|
|
} |
249 |
|
|
|
250 |
|
|
/** |
251 |
|
|
* Inserts all of the elements in the specified collection into this |
252 |
|
|
* list, starting at the specified position. Shifts the element |
253 |
|
|
* currently at that position (if any) and any subsequent elements to |
254 |
|
|
* the right (increases their indices). The new elements will appear |
255 |
|
|
* in the list in the order that they are returned by the |
256 |
|
|
* specified collection's iterator. |
257 |
|
|
* |
258 |
jsr166 |
1.27 |
* @param index index at which to insert the first element |
259 |
|
|
* from the specified collection |
260 |
jsr166 |
1.31 |
* @param c collection containing elements to be added to this list |
261 |
jsr166 |
1.27 |
* @return <tt>true</tt> if this list changed as a result of the call |
262 |
jsr166 |
1.28 |
* @throws IndexOutOfBoundsException {@inheritDoc} |
263 |
jsr166 |
1.27 |
* @throws NullPointerException if the specified collection is null |
264 |
tim |
1.1 |
*/ |
265 |
dl |
1.3 |
public boolean addAll(int index, Collection<? extends E> c) { |
266 |
dl |
1.4 |
if (index < 0 || index > size) |
267 |
dl |
1.3 |
throw new IndexOutOfBoundsException("Index: "+index+ |
268 |
|
|
", Size: "+size); |
269 |
|
|
Object[] a = c.toArray(); |
270 |
|
|
int numNew = a.length; |
271 |
|
|
if (numNew==0) |
272 |
|
|
return false; |
273 |
jsr166 |
1.14 |
modCount++; |
274 |
dl |
1.3 |
|
275 |
|
|
Entry<E> successor = (index==size ? header : entry(index)); |
276 |
|
|
Entry<E> predecessor = successor.previous; |
277 |
jsr166 |
1.14 |
for (int i=0; i<numNew; i++) { |
278 |
dl |
1.3 |
Entry<E> e = new Entry<E>((E)a[i], successor, predecessor); |
279 |
tim |
1.1 |
predecessor.next = e; |
280 |
|
|
predecessor = e; |
281 |
|
|
} |
282 |
|
|
successor.previous = predecessor; |
283 |
|
|
|
284 |
|
|
size += numNew; |
285 |
|
|
return true; |
286 |
|
|
} |
287 |
|
|
|
288 |
|
|
/** |
289 |
|
|
* Removes all of the elements from this list. |
290 |
|
|
*/ |
291 |
|
|
public void clear() { |
292 |
jsr166 |
1.14 |
Entry<E> e = header.next; |
293 |
|
|
while (e != header) { |
294 |
|
|
Entry<E> next = e.next; |
295 |
|
|
e.next = e.previous = null; |
296 |
|
|
e.element = null; |
297 |
|
|
e = next; |
298 |
|
|
} |
299 |
tim |
1.1 |
header.next = header.previous = header; |
300 |
jozart |
1.12 |
size = 0; |
301 |
jsr166 |
1.14 |
modCount++; |
302 |
tim |
1.1 |
} |
303 |
|
|
|
304 |
|
|
|
305 |
|
|
// Positional Access Operations |
306 |
|
|
|
307 |
|
|
/** |
308 |
|
|
* Returns the element at the specified position in this list. |
309 |
|
|
* |
310 |
jsr166 |
1.28 |
* @param index index of the element to return |
311 |
jsr166 |
1.27 |
* @return the element at the specified position in this list |
312 |
jsr166 |
1.28 |
* @throws IndexOutOfBoundsException {@inheritDoc} |
313 |
tim |
1.1 |
*/ |
314 |
dl |
1.3 |
public E get(int index) { |
315 |
tim |
1.1 |
return entry(index).element; |
316 |
|
|
} |
317 |
|
|
|
318 |
|
|
/** |
319 |
|
|
* Replaces the element at the specified position in this list with the |
320 |
|
|
* specified element. |
321 |
|
|
* |
322 |
jsr166 |
1.28 |
* @param index index of the element to replace |
323 |
jsr166 |
1.27 |
* @param element element to be stored at the specified position |
324 |
|
|
* @return the element previously at the specified position |
325 |
jsr166 |
1.28 |
* @throws IndexOutOfBoundsException {@inheritDoc} |
326 |
tim |
1.1 |
*/ |
327 |
dl |
1.3 |
public E set(int index, E element) { |
328 |
|
|
Entry<E> e = entry(index); |
329 |
|
|
E oldVal = e.element; |
330 |
tim |
1.1 |
e.element = element; |
331 |
|
|
return oldVal; |
332 |
|
|
} |
333 |
|
|
|
334 |
|
|
/** |
335 |
|
|
* Inserts the specified element at the specified position in this list. |
336 |
|
|
* Shifts the element currently at that position (if any) and any |
337 |
|
|
* subsequent elements to the right (adds one to their indices). |
338 |
|
|
* |
339 |
jsr166 |
1.27 |
* @param index index at which the specified element is to be inserted |
340 |
|
|
* @param element element to be inserted |
341 |
jsr166 |
1.28 |
* @throws IndexOutOfBoundsException {@inheritDoc} |
342 |
tim |
1.1 |
*/ |
343 |
dl |
1.3 |
public void add(int index, E element) { |
344 |
tim |
1.1 |
addBefore(element, (index==size ? header : entry(index))); |
345 |
|
|
} |
346 |
|
|
|
347 |
|
|
/** |
348 |
|
|
* Removes the element at the specified position in this list. Shifts any |
349 |
|
|
* subsequent elements to the left (subtracts one from their indices). |
350 |
|
|
* Returns the element that was removed from the list. |
351 |
|
|
* |
352 |
jsr166 |
1.27 |
* @param index the index of the element to be removed |
353 |
|
|
* @return the element previously at the specified position |
354 |
jsr166 |
1.28 |
* @throws IndexOutOfBoundsException {@inheritDoc} |
355 |
tim |
1.1 |
*/ |
356 |
dl |
1.3 |
public E remove(int index) { |
357 |
jsr166 |
1.14 |
return remove(entry(index)); |
358 |
tim |
1.1 |
} |
359 |
|
|
|
360 |
|
|
/** |
361 |
jsr166 |
1.24 |
* Returns the indexed entry. |
362 |
tim |
1.1 |
*/ |
363 |
dl |
1.3 |
private Entry<E> entry(int index) { |
364 |
tim |
1.1 |
if (index < 0 || index >= size) |
365 |
|
|
throw new IndexOutOfBoundsException("Index: "+index+ |
366 |
|
|
", Size: "+size); |
367 |
dl |
1.3 |
Entry<E> e = header; |
368 |
tim |
1.1 |
if (index < (size >> 1)) { |
369 |
|
|
for (int i = 0; i <= index; i++) |
370 |
|
|
e = e.next; |
371 |
|
|
} else { |
372 |
|
|
for (int i = size; i > index; i--) |
373 |
|
|
e = e.previous; |
374 |
|
|
} |
375 |
|
|
return e; |
376 |
|
|
} |
377 |
|
|
|
378 |
|
|
|
379 |
|
|
// Search Operations |
380 |
|
|
|
381 |
|
|
/** |
382 |
jsr166 |
1.29 |
* Returns the index of the first occurrence of the specified element |
383 |
|
|
* in this list, or -1 if this list does not contain the element. |
384 |
|
|
* More formally, returns the lowest index <tt>i</tt> such that |
385 |
|
|
* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt>, |
386 |
|
|
* or -1 if there is no such index. |
387 |
tim |
1.1 |
* |
388 |
jsr166 |
1.27 |
* @param o element to search for |
389 |
jsr166 |
1.29 |
* @return the index of the first occurrence of the specified element in |
390 |
|
|
* this list, or -1 if this list does not contain the element |
391 |
tim |
1.1 |
*/ |
392 |
|
|
public int indexOf(Object o) { |
393 |
|
|
int index = 0; |
394 |
|
|
if (o==null) { |
395 |
|
|
for (Entry e = header.next; e != header; e = e.next) { |
396 |
|
|
if (e.element==null) |
397 |
|
|
return index; |
398 |
|
|
index++; |
399 |
|
|
} |
400 |
|
|
} else { |
401 |
|
|
for (Entry e = header.next; e != header; e = e.next) { |
402 |
|
|
if (o.equals(e.element)) |
403 |
|
|
return index; |
404 |
|
|
index++; |
405 |
|
|
} |
406 |
|
|
} |
407 |
|
|
return -1; |
408 |
|
|
} |
409 |
|
|
|
410 |
|
|
/** |
411 |
jsr166 |
1.29 |
* Returns the index of the last occurrence of the specified element |
412 |
|
|
* in this list, or -1 if this list does not contain the element. |
413 |
|
|
* More formally, returns the highest index <tt>i</tt> such that |
414 |
|
|
* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt>, |
415 |
|
|
* or -1 if there is no such index. |
416 |
tim |
1.1 |
* |
417 |
jsr166 |
1.27 |
* @param o element to search for |
418 |
jsr166 |
1.29 |
* @return the index of the last occurrence of the specified element in |
419 |
|
|
* this list, or -1 if this list does not contain the element |
420 |
tim |
1.1 |
*/ |
421 |
|
|
public int lastIndexOf(Object o) { |
422 |
|
|
int index = size; |
423 |
|
|
if (o==null) { |
424 |
|
|
for (Entry e = header.previous; e != header; e = e.previous) { |
425 |
|
|
index--; |
426 |
|
|
if (e.element==null) |
427 |
|
|
return index; |
428 |
|
|
} |
429 |
|
|
} else { |
430 |
|
|
for (Entry e = header.previous; e != header; e = e.previous) { |
431 |
|
|
index--; |
432 |
|
|
if (o.equals(e.element)) |
433 |
|
|
return index; |
434 |
|
|
} |
435 |
|
|
} |
436 |
|
|
return -1; |
437 |
|
|
} |
438 |
|
|
|
439 |
dl |
1.3 |
// Queue operations. |
440 |
|
|
|
441 |
|
|
/** |
442 |
dl |
1.7 |
* Retrieves, but does not remove, the head (first element) of this list. |
443 |
jsr166 |
1.27 |
* @return the head of this list, or <tt>null</tt> if this list is empty |
444 |
dl |
1.7 |
* @since 1.5 |
445 |
dl |
1.3 |
*/ |
446 |
|
|
public E peek() { |
447 |
|
|
if (size==0) |
448 |
|
|
return null; |
449 |
|
|
return getFirst(); |
450 |
|
|
} |
451 |
|
|
|
452 |
|
|
/** |
453 |
dl |
1.7 |
* Retrieves, but does not remove, the head (first element) of this list. |
454 |
jsr166 |
1.27 |
* @return the head of this list |
455 |
|
|
* @throws NoSuchElementException if this list is empty |
456 |
dl |
1.7 |
* @since 1.5 |
457 |
dl |
1.3 |
*/ |
458 |
|
|
public E element() { |
459 |
|
|
return getFirst(); |
460 |
|
|
} |
461 |
|
|
|
462 |
|
|
/** |
463 |
jsr166 |
1.27 |
* Retrieves and removes the head (first element) of this list |
464 |
|
|
* @return the head of this list, or <tt>null</tt> if this list is empty |
465 |
dl |
1.7 |
* @since 1.5 |
466 |
dl |
1.3 |
*/ |
467 |
|
|
public E poll() { |
468 |
|
|
if (size==0) |
469 |
|
|
return null; |
470 |
|
|
return removeFirst(); |
471 |
|
|
} |
472 |
|
|
|
473 |
|
|
/** |
474 |
dl |
1.7 |
* Retrieves and removes the head (first element) of this list. |
475 |
jsr166 |
1.27 |
* |
476 |
|
|
* @return the head of this list |
477 |
|
|
* @throws NoSuchElementException if this list is empty |
478 |
dl |
1.7 |
* @since 1.5 |
479 |
dl |
1.3 |
*/ |
480 |
|
|
public E remove() { |
481 |
|
|
return removeFirst(); |
482 |
|
|
} |
483 |
|
|
|
484 |
|
|
/** |
485 |
|
|
* Adds the specified element as the tail (last element) of this list. |
486 |
|
|
* |
487 |
jsr166 |
1.27 |
* @param e the element to add |
488 |
|
|
* @return <tt>true</tt> (as per the spec for {@link Queue#offer}) |
489 |
dl |
1.7 |
* @since 1.5 |
490 |
dl |
1.3 |
*/ |
491 |
jsr166 |
1.26 |
public boolean offer(E e) { |
492 |
|
|
return add(e); |
493 |
dl |
1.3 |
} |
494 |
|
|
|
495 |
dl |
1.17 |
// Deque operations |
496 |
|
|
/** |
497 |
dl |
1.22 |
* Inserts the specified element at the front of this list. |
498 |
dl |
1.17 |
* |
499 |
dl |
1.22 |
* @param e the element to insert |
500 |
dl |
1.17 |
* @return <tt>true</tt> (as per the spec for {@link Deque#offerFirst}) |
501 |
|
|
* @since 1.6 |
502 |
|
|
*/ |
503 |
dl |
1.22 |
public boolean offerFirst(E e) { |
504 |
|
|
addFirst(e); |
505 |
dl |
1.17 |
return true; |
506 |
|
|
} |
507 |
|
|
|
508 |
|
|
/** |
509 |
dl |
1.22 |
* Inserts the specified element at the end of this list. |
510 |
dl |
1.17 |
* |
511 |
dl |
1.22 |
* @param e the element to insert |
512 |
dl |
1.17 |
* @return <tt>true</tt> (as per the spec for {@link Deque#offerLast}) |
513 |
|
|
* @since 1.6 |
514 |
|
|
*/ |
515 |
dl |
1.22 |
public boolean offerLast(E e) { |
516 |
|
|
addLast(e); |
517 |
dl |
1.17 |
return true; |
518 |
|
|
} |
519 |
|
|
|
520 |
|
|
/** |
521 |
dl |
1.19 |
* Retrieves, but does not remove, the first element of this list, |
522 |
jsr166 |
1.27 |
* or returns <tt>null</tt> if this list is empty. |
523 |
dl |
1.17 |
* |
524 |
jsr166 |
1.27 |
* @return the first element of this list, or <tt>null</tt> |
525 |
jsr166 |
1.28 |
* if this list is empty |
526 |
dl |
1.17 |
* @since 1.6 |
527 |
|
|
*/ |
528 |
|
|
public E peekFirst() { |
529 |
|
|
if (size==0) |
530 |
|
|
return null; |
531 |
dl |
1.18 |
return getFirst(); |
532 |
dl |
1.17 |
} |
533 |
|
|
|
534 |
|
|
/** |
535 |
dl |
1.19 |
* Retrieves, but does not remove, the last element of this list, |
536 |
jsr166 |
1.27 |
* or returns <tt>null</tt> if this list is empty. |
537 |
dl |
1.17 |
* |
538 |
jsr166 |
1.27 |
* @return the last element of this list, or <tt>null</tt> |
539 |
jsr166 |
1.28 |
* if this list is empty |
540 |
dl |
1.17 |
* @since 1.6 |
541 |
|
|
*/ |
542 |
|
|
public E peekLast() { |
543 |
|
|
if (size==0) |
544 |
|
|
return null; |
545 |
dl |
1.18 |
return getLast(); |
546 |
dl |
1.17 |
} |
547 |
|
|
|
548 |
|
|
/** |
549 |
dl |
1.19 |
* Retrieves and removes the first element of this list, or |
550 |
|
|
* <tt>null</tt> if this list is empty. |
551 |
dl |
1.17 |
* |
552 |
dl |
1.19 |
* @return the first element of this list, or <tt>null</tt> if |
553 |
|
|
* this list is empty |
554 |
dl |
1.17 |
* @since 1.6 |
555 |
|
|
*/ |
556 |
|
|
public E pollFirst() { |
557 |
|
|
if (size==0) |
558 |
|
|
return null; |
559 |
|
|
return removeFirst(); |
560 |
|
|
} |
561 |
|
|
|
562 |
|
|
/** |
563 |
dl |
1.19 |
* Retrieves and removes the last element of this list, or |
564 |
|
|
* <tt>null</tt> if this list is empty. |
565 |
dl |
1.17 |
* |
566 |
dl |
1.19 |
* @return the last element of this list, or <tt>null</tt> if |
567 |
|
|
* this list is empty |
568 |
dl |
1.17 |
* @since 1.6 |
569 |
|
|
*/ |
570 |
|
|
public E pollLast() { |
571 |
|
|
if (size==0) |
572 |
|
|
return null; |
573 |
|
|
return removeLast(); |
574 |
|
|
} |
575 |
|
|
|
576 |
|
|
/** |
577 |
dl |
1.19 |
* Pushes an element onto the stack represented by this list. In other |
578 |
dl |
1.22 |
* words, inserts the element at the front of this list. |
579 |
dl |
1.17 |
* |
580 |
|
|
* <p>This method is equivalent to {@link #addFirst}. |
581 |
|
|
* |
582 |
dl |
1.22 |
* @param e the element to push |
583 |
dl |
1.17 |
* @since 1.6 |
584 |
|
|
*/ |
585 |
dl |
1.22 |
public void push(E e) { |
586 |
|
|
addFirst(e); |
587 |
dl |
1.17 |
} |
588 |
|
|
|
589 |
|
|
/** |
590 |
dl |
1.19 |
* Pops an element from the stack represented by this list. In other |
591 |
dl |
1.20 |
* words, removes and returns the first element of this list. |
592 |
dl |
1.17 |
* |
593 |
|
|
* <p>This method is equivalent to {@link #removeFirst()}. |
594 |
|
|
* |
595 |
dl |
1.19 |
* @return the element at the front of this list (which is the top |
596 |
jsr166 |
1.27 |
* of the stack represented by this list) |
597 |
|
|
* @throws NoSuchElementException if this list is empty |
598 |
dl |
1.17 |
* @since 1.6 |
599 |
|
|
*/ |
600 |
|
|
public E pop() { |
601 |
|
|
return removeFirst(); |
602 |
|
|
} |
603 |
|
|
|
604 |
|
|
/** |
605 |
|
|
* Removes the first occurrence of the specified element in this |
606 |
dl |
1.19 |
* list (when traversing the list from head to tail). If the list |
607 |
dl |
1.17 |
* does not contain the element, it is unchanged. |
608 |
|
|
* |
609 |
dl |
1.21 |
* @param o element to be removed from this list, if present |
610 |
dl |
1.19 |
* @return <tt>true</tt> if the list contained the specified element |
611 |
dl |
1.17 |
* @since 1.6 |
612 |
|
|
*/ |
613 |
dl |
1.21 |
public boolean removeFirstOccurrence(Object o) { |
614 |
|
|
return remove(o); |
615 |
dl |
1.17 |
} |
616 |
|
|
|
617 |
|
|
/** |
618 |
|
|
* Removes the last occurrence of the specified element in this |
619 |
dl |
1.19 |
* list (when traversing the list from head to tail). If the list |
620 |
dl |
1.17 |
* does not contain the element, it is unchanged. |
621 |
|
|
* |
622 |
dl |
1.19 |
* @param o element to be removed from this list, if present |
623 |
|
|
* @return <tt>true</tt> if the list contained the specified element |
624 |
dl |
1.17 |
* @since 1.6 |
625 |
|
|
*/ |
626 |
|
|
public boolean removeLastOccurrence(Object o) { |
627 |
|
|
if (o==null) { |
628 |
dl |
1.34 |
for (Entry<E> e = header.previous; e != header; e = e.previous) { |
629 |
dl |
1.17 |
if (e.element==null) { |
630 |
|
|
remove(e); |
631 |
|
|
return true; |
632 |
|
|
} |
633 |
|
|
} |
634 |
|
|
} else { |
635 |
dl |
1.34 |
for (Entry<E> e = header.previous; e != header; e = e.previous) { |
636 |
dl |
1.17 |
if (o.equals(e.element)) { |
637 |
|
|
remove(e); |
638 |
|
|
return true; |
639 |
|
|
} |
640 |
|
|
} |
641 |
|
|
} |
642 |
|
|
return false; |
643 |
|
|
} |
644 |
|
|
|
645 |
tim |
1.1 |
/** |
646 |
|
|
* Returns a list-iterator of the elements in this list (in proper |
647 |
|
|
* sequence), starting at the specified position in the list. |
648 |
|
|
* Obeys the general contract of <tt>List.listIterator(int)</tt>.<p> |
649 |
|
|
* |
650 |
|
|
* The list-iterator is <i>fail-fast</i>: if the list is structurally |
651 |
|
|
* modified at any time after the Iterator is created, in any way except |
652 |
|
|
* through the list-iterator's own <tt>remove</tt> or <tt>add</tt> |
653 |
|
|
* methods, the list-iterator will throw a |
654 |
|
|
* <tt>ConcurrentModificationException</tt>. Thus, in the face of |
655 |
|
|
* concurrent modification, the iterator fails quickly and cleanly, rather |
656 |
|
|
* than risking arbitrary, non-deterministic behavior at an undetermined |
657 |
|
|
* time in the future. |
658 |
|
|
* |
659 |
jsr166 |
1.27 |
* @param index index of the first element to be returned from the |
660 |
jsr166 |
1.28 |
* list-iterator (by a call to <tt>next</tt>) |
661 |
tim |
1.1 |
* @return a ListIterator of the elements in this list (in proper |
662 |
jsr166 |
1.28 |
* sequence), starting at the specified position in the list |
663 |
|
|
* @throws IndexOutOfBoundsException {@inheritDoc} |
664 |
dl |
1.3 |
* @see List#listIterator(int) |
665 |
tim |
1.1 |
*/ |
666 |
dl |
1.3 |
public ListIterator<E> listIterator(int index) { |
667 |
jsr166 |
1.14 |
return new ListItr(index); |
668 |
tim |
1.1 |
} |
669 |
|
|
|
670 |
dl |
1.3 |
private class ListItr implements ListIterator<E> { |
671 |
jsr166 |
1.14 |
private Entry<E> lastReturned = header; |
672 |
|
|
private Entry<E> next; |
673 |
|
|
private int nextIndex; |
674 |
|
|
private int expectedModCount = modCount; |
675 |
|
|
|
676 |
|
|
ListItr(int index) { |
677 |
|
|
if (index < 0 || index > size) |
678 |
|
|
throw new IndexOutOfBoundsException("Index: "+index+ |
679 |
|
|
", Size: "+size); |
680 |
|
|
if (index < (size >> 1)) { |
681 |
|
|
next = header.next; |
682 |
|
|
for (nextIndex=0; nextIndex<index; nextIndex++) |
683 |
|
|
next = next.next; |
684 |
|
|
} else { |
685 |
|
|
next = header; |
686 |
|
|
for (nextIndex=size; nextIndex>index; nextIndex--) |
687 |
|
|
next = next.previous; |
688 |
|
|
} |
689 |
|
|
} |
690 |
|
|
|
691 |
|
|
public boolean hasNext() { |
692 |
|
|
return nextIndex != size; |
693 |
|
|
} |
694 |
|
|
|
695 |
|
|
public E next() { |
696 |
|
|
checkForComodification(); |
697 |
|
|
if (nextIndex == size) |
698 |
|
|
throw new NoSuchElementException(); |
699 |
|
|
|
700 |
|
|
lastReturned = next; |
701 |
|
|
next = next.next; |
702 |
|
|
nextIndex++; |
703 |
|
|
return lastReturned.element; |
704 |
|
|
} |
705 |
|
|
|
706 |
|
|
public boolean hasPrevious() { |
707 |
|
|
return nextIndex != 0; |
708 |
|
|
} |
709 |
|
|
|
710 |
|
|
public E previous() { |
711 |
|
|
if (nextIndex == 0) |
712 |
|
|
throw new NoSuchElementException(); |
713 |
|
|
|
714 |
|
|
lastReturned = next = next.previous; |
715 |
|
|
nextIndex--; |
716 |
|
|
checkForComodification(); |
717 |
|
|
return lastReturned.element; |
718 |
|
|
} |
719 |
|
|
|
720 |
|
|
public int nextIndex() { |
721 |
|
|
return nextIndex; |
722 |
|
|
} |
723 |
|
|
|
724 |
|
|
public int previousIndex() { |
725 |
|
|
return nextIndex-1; |
726 |
|
|
} |
727 |
jozart |
1.12 |
|
728 |
jsr166 |
1.14 |
public void remove() { |
729 |
tim |
1.1 |
checkForComodification(); |
730 |
jsr166 |
1.14 |
Entry<E> lastNext = lastReturned.next; |
731 |
tim |
1.1 |
try { |
732 |
|
|
LinkedList.this.remove(lastReturned); |
733 |
|
|
} catch (NoSuchElementException e) { |
734 |
|
|
throw new IllegalStateException(); |
735 |
|
|
} |
736 |
jsr166 |
1.14 |
if (next==lastReturned) |
737 |
|
|
next = lastNext; |
738 |
tim |
1.1 |
else |
739 |
jsr166 |
1.14 |
nextIndex--; |
740 |
|
|
lastReturned = header; |
741 |
|
|
expectedModCount++; |
742 |
|
|
} |
743 |
|
|
|
744 |
jsr166 |
1.26 |
public void set(E e) { |
745 |
jsr166 |
1.14 |
if (lastReturned == header) |
746 |
|
|
throw new IllegalStateException(); |
747 |
|
|
checkForComodification(); |
748 |
jsr166 |
1.26 |
lastReturned.element = e; |
749 |
jsr166 |
1.14 |
} |
750 |
|
|
|
751 |
jsr166 |
1.26 |
public void add(E e) { |
752 |
jsr166 |
1.14 |
checkForComodification(); |
753 |
|
|
lastReturned = header; |
754 |
jsr166 |
1.26 |
addBefore(e, next); |
755 |
jsr166 |
1.14 |
nextIndex++; |
756 |
|
|
expectedModCount++; |
757 |
|
|
} |
758 |
|
|
|
759 |
|
|
final void checkForComodification() { |
760 |
|
|
if (modCount != expectedModCount) |
761 |
|
|
throw new ConcurrentModificationException(); |
762 |
|
|
} |
763 |
dl |
1.3 |
} |
764 |
|
|
|
765 |
|
|
private static class Entry<E> { |
766 |
jsr166 |
1.14 |
E element; |
767 |
|
|
Entry<E> next; |
768 |
|
|
Entry<E> previous; |
769 |
|
|
|
770 |
|
|
Entry(E element, Entry<E> next, Entry<E> previous) { |
771 |
|
|
this.element = element; |
772 |
|
|
this.next = next; |
773 |
|
|
this.previous = previous; |
774 |
|
|
} |
775 |
dl |
1.3 |
} |
776 |
|
|
|
777 |
jsr166 |
1.26 |
private Entry<E> addBefore(E e, Entry<E> entry) { |
778 |
|
|
Entry<E> newEntry = new Entry<E>(e, entry, entry.previous); |
779 |
jsr166 |
1.14 |
newEntry.previous.next = newEntry; |
780 |
|
|
newEntry.next.previous = newEntry; |
781 |
|
|
size++; |
782 |
|
|
modCount++; |
783 |
|
|
return newEntry; |
784 |
|
|
} |
785 |
|
|
|
786 |
|
|
private E remove(Entry<E> e) { |
787 |
|
|
if (e == header) |
788 |
|
|
throw new NoSuchElementException(); |
789 |
|
|
|
790 |
|
|
E result = e.element; |
791 |
|
|
e.previous.next = e.next; |
792 |
|
|
e.next.previous = e.previous; |
793 |
|
|
e.next = e.previous = null; |
794 |
|
|
e.element = null; |
795 |
|
|
size--; |
796 |
|
|
modCount++; |
797 |
|
|
return result; |
798 |
tim |
1.1 |
} |
799 |
|
|
|
800 |
|
|
/** |
801 |
|
|
* Returns a shallow copy of this <tt>LinkedList</tt>. (The elements |
802 |
|
|
* themselves are not cloned.) |
803 |
|
|
* |
804 |
jsr166 |
1.27 |
* @return a shallow copy of this <tt>LinkedList</tt> instance |
805 |
tim |
1.1 |
*/ |
806 |
|
|
public Object clone() { |
807 |
dl |
1.3 |
LinkedList<E> clone = null; |
808 |
jsr166 |
1.14 |
try { |
809 |
|
|
clone = (LinkedList<E>) super.clone(); |
810 |
|
|
} catch (CloneNotSupportedException e) { |
811 |
|
|
throw new InternalError(); |
812 |
|
|
} |
813 |
tim |
1.1 |
|
814 |
|
|
// Put clone into "virgin" state |
815 |
dl |
1.3 |
clone.header = new Entry<E>(null, null, null); |
816 |
tim |
1.1 |
clone.header.next = clone.header.previous = clone.header; |
817 |
|
|
clone.size = 0; |
818 |
|
|
clone.modCount = 0; |
819 |
|
|
|
820 |
|
|
// Initialize clone with our elements |
821 |
dl |
1.3 |
for (Entry<E> e = header.next; e != header; e = e.next) |
822 |
tim |
1.1 |
clone.add(e.element); |
823 |
|
|
|
824 |
|
|
return clone; |
825 |
|
|
} |
826 |
|
|
|
827 |
|
|
/** |
828 |
|
|
* Returns an array containing all of the elements in this list |
829 |
jsr166 |
1.29 |
* in proper sequence (from first to last element). |
830 |
tim |
1.1 |
* |
831 |
jsr166 |
1.29 |
* <p>The returned array will be "safe" in that no references to it are |
832 |
|
|
* maintained by this list. (In other words, this method must allocate |
833 |
|
|
* a new array). The caller is thus free to modify the returned array. |
834 |
jsr166 |
1.32 |
* |
835 |
jsr166 |
1.30 |
* <p>This method acts as bridge between array-based and collection-based |
836 |
|
|
* APIs. |
837 |
|
|
* |
838 |
tim |
1.1 |
* @return an array containing all of the elements in this list |
839 |
jsr166 |
1.29 |
* in proper sequence |
840 |
tim |
1.1 |
*/ |
841 |
|
|
public Object[] toArray() { |
842 |
jsr166 |
1.14 |
Object[] result = new Object[size]; |
843 |
tim |
1.1 |
int i = 0; |
844 |
dl |
1.3 |
for (Entry<E> e = header.next; e != header; e = e.next) |
845 |
tim |
1.1 |
result[i++] = e.element; |
846 |
jsr166 |
1.14 |
return result; |
847 |
tim |
1.1 |
} |
848 |
|
|
|
849 |
|
|
/** |
850 |
|
|
* Returns an array containing all of the elements in this list in |
851 |
jsr166 |
1.29 |
* proper sequence (from first to last element); the runtime type of |
852 |
|
|
* the returned array is that of the specified array. If the list fits |
853 |
|
|
* in the specified array, it is returned therein. Otherwise, a new |
854 |
|
|
* array is allocated with the runtime type of the specified array and |
855 |
|
|
* the size of this list. |
856 |
|
|
* |
857 |
|
|
* <p>If the list fits in the specified array with room to spare (i.e., |
858 |
|
|
* the array has more elements than the list), the element in the array |
859 |
|
|
* immediately following the end of the list is set to <tt>null</tt>. |
860 |
|
|
* (This is useful in determining the length of the list <i>only</i> if |
861 |
|
|
* the caller knows that the list does not contain any null elements.) |
862 |
|
|
* |
863 |
|
|
* <p>Like the {@link #toArray()} method, this method acts as bridge between |
864 |
|
|
* array-based and collection-based APIs. Further, this method allows |
865 |
|
|
* precise control over the runtime type of the output array, and may, |
866 |
|
|
* under certain circumstances, be used to save allocation costs. |
867 |
|
|
* |
868 |
|
|
* <p>Suppose <tt>x</tt> is a list known to contain only strings. |
869 |
|
|
* The following code can be used to dump the list into a newly |
870 |
|
|
* allocated array of <tt>String</tt>: |
871 |
|
|
* |
872 |
|
|
* <pre> |
873 |
|
|
* String[] y = x.toArray(new String[0]);</pre> |
874 |
|
|
* |
875 |
|
|
* Note that <tt>toArray(new Object[0])</tt> is identical in function to |
876 |
|
|
* <tt>toArray()</tt>. |
877 |
tim |
1.1 |
* |
878 |
|
|
* @param a the array into which the elements of the list are to |
879 |
jsr166 |
1.27 |
* be stored, if it is big enough; otherwise, a new array of the |
880 |
|
|
* same runtime type is allocated for this purpose. |
881 |
|
|
* @return an array containing the elements of the list |
882 |
jsr166 |
1.29 |
* @throws ArrayStoreException if the runtime type of the specified array |
883 |
|
|
* is not a supertype of the runtime type of every element in |
884 |
|
|
* this list |
885 |
jsr166 |
1.27 |
* @throws NullPointerException if the specified array is null |
886 |
tim |
1.1 |
*/ |
887 |
dl |
1.3 |
public <T> T[] toArray(T[] a) { |
888 |
tim |
1.1 |
if (a.length < size) |
889 |
dl |
1.3 |
a = (T[])java.lang.reflect.Array.newInstance( |
890 |
tim |
1.1 |
a.getClass().getComponentType(), size); |
891 |
|
|
int i = 0; |
892 |
jsr166 |
1.14 |
Object[] result = a; |
893 |
dl |
1.3 |
for (Entry<E> e = header.next; e != header; e = e.next) |
894 |
|
|
result[i++] = e.element; |
895 |
tim |
1.1 |
|
896 |
|
|
if (a.length > size) |
897 |
|
|
a[size] = null; |
898 |
|
|
|
899 |
|
|
return a; |
900 |
|
|
} |
901 |
|
|
|
902 |
|
|
private static final long serialVersionUID = 876323262645176354L; |
903 |
|
|
|
904 |
|
|
/** |
905 |
|
|
* Save the state of this <tt>LinkedList</tt> instance to a stream (that |
906 |
|
|
* is, serialize it). |
907 |
|
|
* |
908 |
|
|
* @serialData The size of the list (the number of elements it |
909 |
jsr166 |
1.27 |
* contains) is emitted (int), followed by all of its |
910 |
|
|
* elements (each an Object) in the proper order. |
911 |
tim |
1.1 |
*/ |
912 |
dl |
1.3 |
private void writeObject(java.io.ObjectOutputStream s) |
913 |
tim |
1.1 |
throws java.io.IOException { |
914 |
jsr166 |
1.14 |
// Write out any hidden serialization magic |
915 |
|
|
s.defaultWriteObject(); |
916 |
tim |
1.1 |
|
917 |
|
|
// Write out size |
918 |
|
|
s.writeInt(size); |
919 |
|
|
|
920 |
jsr166 |
1.14 |
// Write out all elements in the proper order. |
921 |
tim |
1.1 |
for (Entry e = header.next; e != header; e = e.next) |
922 |
|
|
s.writeObject(e.element); |
923 |
|
|
} |
924 |
|
|
|
925 |
|
|
/** |
926 |
|
|
* Reconstitute this <tt>LinkedList</tt> instance from a stream (that is |
927 |
|
|
* deserialize it). |
928 |
|
|
*/ |
929 |
dl |
1.3 |
private void readObject(java.io.ObjectInputStream s) |
930 |
tim |
1.1 |
throws java.io.IOException, ClassNotFoundException { |
931 |
jsr166 |
1.14 |
// Read in any hidden serialization magic |
932 |
|
|
s.defaultReadObject(); |
933 |
tim |
1.1 |
|
934 |
|
|
// Read in size |
935 |
|
|
int size = s.readInt(); |
936 |
|
|
|
937 |
|
|
// Initialize header |
938 |
dl |
1.3 |
header = new Entry<E>(null, null, null); |
939 |
tim |
1.1 |
header.next = header.previous = header; |
940 |
|
|
|
941 |
jsr166 |
1.14 |
// Read in all elements in the proper order. |
942 |
|
|
for (int i=0; i<size; i++) |
943 |
dl |
1.3 |
addBefore((E)s.readObject(), header); |
944 |
tim |
1.1 |
} |
945 |
|
|
} |